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Stripe Ansatzs from Exactly Solved Models

M. A. Martin-Delgado·M. Roncaglia·G. Sierra
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Abstract

Using the Boltzmann weights of classical Statistical Mechanics vertex models we define a new class of Tensor Product Ansatzs for 2D quantum lattice systems, characterized by a strong anisotropy, which gives rise to stripe like structures. In the case of the six vertex model we compute exactly, in the thermodynamic limit, the norm of the ansatz and other observables. Employing this ansatz we study the phase diagram of a Hamiltonian given by the sum of XXZ Hamiltonians along the legs coupled by an Ising term. Finally, we suggest a connection between the six and eight-vertex Anisotropic Tensor Product Ansatzs, and their associated Hamiltonians, with the smectic stripe phases recently discussed in the literature.

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M. A. Martin-Delgado, M. Roncaglia, G. Sierra. 2001-04-06. Stripe Ansatzs from Exactly Solved Models. https://doi.org/10.1103/physrevb.64.075117

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